@*
* Copyright 2019 LinkedIn Corp.
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may not
* use this file except in compliance with the License. You may obtain a copy of
* the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations under
* the License.
*@
<p>
  This heuristic shows how much memory you requested for each task type and what the max memory used
  by any instance of each task type actually was. If the requested memory is within some grace amount
  (default 2 GB) of the max memory, then severity will be none. Otherwise, if the max memory used is
  less than some percentage (by default 80, 70, 60, or 50 percent) of the requested memory, then
  Dr. Elephant will indicate some severity (low, moderate, severe, or critical, respectively).
</p>
<p>
  To reduce the amount of memory requested for a task, you can update <code>tony.X.memory</code>, where
  <code>X</code> is your task type. For example, to request 4 GB for your worker tasks, you can set
  <code>tony.worker.memory=4g</code>. For more information on TonY configurations, please visit the
  <a href="https://github.com/linkedin/TonY/wiki/TonY-Configurations">TonY Configurations Wiki page</a>.
</p>